I will recommend 'Marjorie'. I grow it and it does flower prolifically. I just cut off any bits that I do not want.

'Mayleen' is said to be highly fragranced, but the flowers aren't that different to look at than many other montana varieties - Marjorie, on the other hand, has flowers that are somewhat different in appearance. I'd go for Mayleen because of the fragrance, personally...

Mayleen is also said to be a very fast grower reaching up to 30' with a strong vanilla scent. As Bamboo says Marjorie has semi double flowers which range in colour from almost white to a coppery pink. I think being montanas neither needs a lot of aftercare apart from pruning back unwanted growth after it flowers. Do let us know which one you decide to grow.

Thank you Scotsgran and Bamboo. I do like the difference in colour and flower shape in Marjorie although I read the other day that if you don't get the position right it produces rather green looking blooms. Also I understand it is a less strong grower. My head tells me that is the one to go for but on the other hand I am keen to add scent to the garden so I think Mayleen wins! Just hope I don't regret the rampaging qualities!

You can always cut back excessive growth on Mayleen after the flowers go over. Enjoy the scent.